PGI magazine has a few pages of drills each month
Argos also has a few pages of drills.
The training drills are in the back, near the kiddies toys. I think you can get one with a Bob the Builder set.
When you feel confident enough to use proper drills, I thoroughly recommend a Bosh or Makita.
Later you can step up to the SDS variety.
Preferably fit a Forstner bit, for maximum lethality and scaryness.
In all seriousness, one of the best drills, is trying to hit a target on the break...ie at the opposite end of the field.
Surprising how few people can do it...but of your entire team can consistently hose paint on the break at about waist height at the opposite end field, you will get lots of kills off the break, which makes the rest of the game so much easier.